1. Field of the Invention
The present invention relates to retrieving, sorting, selecting and organizing items in a database, such as an electronic catalog, using comparisons. More particularly, the invention relates to grouping items in the database based on similarity.
2. Description of the Related Art
Searchable electronic catalogs (e-catalogs) are commonly used in support of various electronic commerce and purchasing functions. These catalogs typically have a user interface for selectively retrieving and displaying records as well as a system for electronically purchasing any items that are selected. A critical factor in the acceptance and success of electronic catalogs is how well they allow a user to find a desired item. As electronic catalogs grow and the number of similar items increases, it becomes increasingly harder to compare the items that are available and to find items with a set of desired features.
The conventional finding aids for an e-catalog are a taxonomical hierarchy of categories and classifications of the items and a search engine. The categories can help a user find an item if the classifications are well understood, but once the appropriate sub-grouping is found it does not help the user sort through large numbers of similar items. A search engine will typically allow a user to search for particular key words and then display the search results. The key word search, however, requires that the user know all possible key words that might be used to describe a particular item or feature of the item. If the catalog has a large number of items, it is also likely that undesired, unrelated items will also be found in the search together with the desired types of items.
Once a list of items is retrieved, it is typically displayed as rows of items. The features of the items are often aligned into tables. If the display includes a large number of items, it can still be difficult to navigate through such a table and isolate the key similarities and differences between the items. Various sorting tools have been offered to assist a user in finding a desired item from a large list. When attributes of the items are each listed in a different column, some search systems allow the user to sort the items based on their respective values in a column. Further searches within only the displayed items can be used to restrict the display list to those having only a certain value or range of values for a particular attribute. Some search engines allow for “parametric refinement” in which a particular value for an attribute can be selected. The search engine will then search within the listed items and display only items with the same value as the selected value for the attribute. For comparisons, some search engines can compare items and flag the differences in the display. This is typically applied only to compare two or three items. With a large number of items, there can be many more differences so that too many attributes are flagged to provide a useful result.